12 
fied eau céleste. The latest experiments indicate that the best results 
will follow the use of these preparations when made as follows: 
1.—BORDEAUX MIXTURE, 
In a barrel that will hold 45 gallons dissolve 6 pounds of copper 
sulphate, using 8 or 10 gallons of water or as much as may benecessary for 
the purpose. Ina tubor half barrel slake 4 pounds of fresh lime. When 
completely slaked add enough water to make a creamy whitewash. 
Pour this slowly into the barrel containing the copper-sulphate solu- 
tion, using a coarse gunny sack stretched over the head of the barrel for 
a Strainer. Finally fill the barrel with water, stir thoroughly, and the 
mixture is ready for use. Prepared in this way the cost of 1 gallon 
of the mixture will not exceed 1 cent, the price of copper sulphate 
being 7 cents per pound and lime 30 cents per bushel. In all cases it 
is desirable to use powdered copper sulphate, as it costs but little more 
and dissolves much more readily. Itis highly important also that fresh 
lime be used. 
It will be seen by those familiar with former suggestions made by the 
Department that the strength of this mixture has been diminished one- 
half. It was found as the result of experiments made in 1891 that a 
mixture of this strength, and even much weaker, gave practically as 
good results as the old formula, which required 6 pounds of copper sul- 
phate and 4 pounds of lime to 22 gallons of water. 
2.—AMMONIACAL SOLUTION OF COPPER CARBONATE. 
In an ordinary water pail mix 5 ounces of copper carbonate with 
enough water to make a thick paste. Dissolve this paste in 3 pints of 
strong aqua ammonia; then dilute to 45 gallons. If three pints of am- 
monia are not sufficient to dissolve all the paste add enough to bring 
about this result.. Copper carbonate occurs in the market in the form 
of a fine greenish powder. ‘The retail price is usually 60 cents per 
pound. Aqua ammonia having a strength of 26° retails at 8 cents per 
pound. Upon this basis 1 gallon of the ammoniacal solution of copper 
carbonate will cost 1 cent. 
In view of the fact that copper carbonate is sometimes difficult to ob- 
tain the following directions for manufacturing it are given: 
In a half barrel, or some similar vessel, dissolve 3 pounds of copper 
sulphatein 2 gallons of hot water. In another vessel dissolve 3$ pounds 
of common washing soda or sal soda in 1 gallon of hot water. When 
cool pour the second solution slowly into the first; then as soon as all 
action has ceased add enough water to bring the whole up to 8 or 10 
gallons and stir thoroughly. In twenty-four hours pour off the clear 
liquid, taking care not to disturb thesediment. Add fresh water and 
stir again. Again allow the solution to stand twenty-four hours, pour 
off the clear liquid as before; then remove the sediment, which is cop- 
per carbonate. Prepared in this way there is formed 14 pounds of 
ee ele 
